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Date: Tue, 3 Aug 2004 13:04:55 -0300 (ART)
From: Fernando Gleiser <fgleiser@cactus.fi.uba.ar>
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Subject: Controlling external hardware via lpt0
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First, I apologize if this isn't the right place for asking this things

I need to control some external hardware with a small program in
FreeBSD. I thought about using the 8 data bits of the parallel port
for sending the control bits  to the hardware.
The hardware is a very simple combinational logic, triggered by level,
I don't need any flow control or such.

The soft opens /dev/lpt0 and then writes whatever value is needed (i.e,
if I need the 2 lsb to be high and the rest low, I write 0x3)

The problem is, I can't even open the paralel port for writing, it
always fails with EBUSY.

on the parallel port I attached a DB-25 wired as a "dummy printer", that
is: strobe->/ack, busy, paper end and select inh, wired together and
then sent to pin 18 (GND).

Is there anything I'm missing? Are there a "programming and using the
parallel port in FreeBSD" guide?

Thanks in advance

				Fer